I've done over 1,100 miles on TPV now so I thought it was time I did a comparison with Zwift.
1. Graphics. No contest, Zwift is greatly superior.
2. Ease of use. Probably similar but I've found TPV very easy to pick up so would say it is slightly better.
3. Physics/dynamics. Here I much prefer TPV. It feels a lot more realistic. Breaks happen easier, wind is a factor and corners require you to slow up.
4. Gamification. This one is easy as TPV has none, other than ticking off routes when you complete them.
5. Worlds/ Roads. Not sure of the exact numbers but Zwift has loads more roads and multiple worlds.
6. Socials. Facilities are similar but there are many more users on Zwift. I've joined a friendly club with 300+ members. It is much easier to create clubs in TPV and anyone can create a club kit which can then be used.
7. Workouts. Not sure why but I prefer workouts on TPV.
8. Customisation. TPV is the winner. Just about everything is customisable and you have access to data like torque.
9. Racing. Zwift has much more choice (if you only want to race real people) with many more organised events. TPV has variety such as Elimination races which are fun. I prefer the physics in TPV.
10. Bots. This may be a Marmite point. TPV has 10,000 bots each with their own power curve and w' etc. They look like real people on screen. They are around a lot in free rides and pacing groups but you can exclude them in any organised rides or races. Apparently you soon learn the characteristics of some of them that you see regularly. One benefit is that you can arrange races at the drop of a hat and the bots will populate them if not enough real riders sign up. E. G. I could arrange a race in 30 minutes time if I wanted.
11. Price. No brainier at the minute as TVP is free. Come March it will cost whatever Training Peaks Premium costs which is not loads, especially with the various discounts that get offered, but not nothing either.
So, in summary I think both are great platforms. For serious indoor riders, there is a strong case for having both.