Talk to me about Training Peaks...

I use TP mainly for planning, and a little analysis. I do most of my analysis via Golden Cheetah for the bike. I don't do any analysis for swimming or running. Garmin Connect is pretty weak on analysis. Golden Cheetah is free and a good option.

The reason I switched to TP was for the virtual coach option. I use the virtual coach and annual training plan to set up my training and periodize my training. The cost for a year of TP is about t cost of one month of training, so I thought this option would be best.

TP is also popular with coaches because they can look at and analyze the training of their clients without requiring them to send in files.

I've been using TP for about 6 years now and love it!  It has its issues (still very heavy on flash, so gets slow sometimes), but other then that works great. 

Been using it for last 3 years or so with power now, and it does have TONS of tools to analyze your workouts.  I would even say too many to where a lot of people fall into the "analysis - paralysis" trap.  

But as someone else mentioned it does calculate TSS for running and swimming also, so if you put all your thresholds in correctly and update accordingly, its a great tool to track your fitness and fine tune your taper for your A races. 

I started using TP when I bought my TGT watch, simply because that's what it exported to.

I log my workouts here, but when I'm trying to watch my calories and cut a few lbs. and really like their food log and calorie counter for workouts.

As you can probably guess it's mostly personal preference for that kind of stuff because you can do the same things here.

I have a love hate relationship with it.  I think the BT logs are the best out there.  But they have a ways to go before they have the analytical tools I need. 

As a coach, I like TP.  It makes my life much easier.  As an athlete, eh.  I use it because my coach uses it.  Before hiring him, I didn't upload my data for over 3 years to TP.  There was no need and the functionality was a pain. 

Aside from the other points made in the answer to the question, I specifically like that TP has it all integrated - planning, results, analysis, food (one of the best calorie tracking options in my opinion). I also take in my regular biometrics and TP supports that too, though not all the fields that my segmental scale provides.  

For specifics on analysis I'm toying with WKO+ and a trial version of the physfarm product.  I look at Garmin connect once in awhile, especially for my swim results in pool swimming where I can get length by length results from my 910xt displayed.

I'm only now getting into understanding TSS, but it seems TP has that covered.

I've never used BT logs so don't know what I"m missing or whether they are better or worse than TP.

I signed up for TP years ago and got the free account. I logged in a couple times and was like meh' whatevers and never logged back in again.

Fast forward to now and I have Ironman Boulder 2019 to train for. So in the process of researching different training methods/sites/coaching, etc...I had a few choices:

(24 month planning)

1) A local coach who wanted $299 for a each of 2 12 week plans, so $598. This did not include any changes, email contact 2x a month, no file analysis. If I wanted the full package it was going to be $400 per month. Well established coach, pro triathlete history, I am sure worth every penny, but WAY TOO RICH for my mortal budget.

2) TriDot, free 2 months introduction package with all the bells and whistles, then you can select a monthly rate that suites your needs after that. I did not want to get into something where I got the full deal up front and then had to sacrifice to the bare bones package after that, or feel like I needed to go with the full package and hurt every month with a potentially unneeded financial hit. There also appeared to be a fairly steep learning curve to their software, and they focused on more intense workouts because of the pressure to get results.

3) Go with a premium TP account with a solid training plan, pay for it all in one shot and focus on training. In the end I found a training plan by Matt Fitzgerald and his 80/20 Endurance training plans. He offers levels 0-4 (0-beginner 4-pro/expert) for all distances. I choose the level 2 140.6 plan. The plan by itself is $84, or for $169 you get the plan plus 6 months of premium TP. 

Advantages:
Training plan is automatically already loaded and ready to go, you just follow along. 
Your completed workouts are automatically uploaded from your Garmin account.
You can download to workouts directly into your Garmin watch or bike computer and simply follow the workout! (Have not tried this yet)
You can create the bike workouts in Trainer Road for doing indoor trainer rides.
You can also purchase the 80/20 Triathlon book and get all workouts in the book for $20 if your so motivated.

So for me it really came down to cost effectiveness, training effectiveness, and ease of implementation. I don't want to focus on software and all the idiosyncrasies involved with the art of training. I simply want to train and train effectively.

Training Peaks combined with a quality training plan allows me to do just that, train, simply and effectively. SO that is the reason after researching several different avenues I went with TP.

www.8020endurance.com