Surely the only difference between an NA and a TT is that the TT is quicker? An NA is still a quick car, from what I've heard is reliable and they look, frankly, stunning - it is a Supra after all.
My daily driver is a SEAT Leon TDi with 150bhp, which I consider to be a quick car. It feels like it has more low-end torque than my TT and feels more responsive (although it probably doesn't/isn't, I expect the performance in the Supra so I notice it less) and is great fun to drive even though it does 0-60 in 8.6. It's not as fast as an NA but it feels fast enough for what I use it for.
If all you want the NA for is commuting/nipping round town/cruising on motorways then you get all the benefits of having an attractive, comfortable, powerful car without needing 'supercar' performance.
Having had experience of a TT, if your friend remembers the performance with longing every time he gets in a Supra then it's not a good idea to get one. If he/she has no preconceptions, it's a great idea.
Also, as Havard says, if your friend is likely (like me) to get addicted to the speed and will feel the draw of getting more power then it's probably not a good idea.
I hate this phrase, but...
At the end of the day *cringe*, if all you want is an attractive, quick, comfortable, fun-to-drive car without the need for excessive power then surely an NA is a great choice - especially for value for money.
Besides, every one talks about so-called 'hot-hatch' performance like it's a bad thing. It's not like that level of performance is low. Normal cars take around 12 seconds to get from 0 to 60. In the region of 6-7 seconds, whether you're in a Golf or a Supra, it's still bloody quick. Just that in a Supra you look damn good while you're doing it
I would have no problems driving around in an NA, personally.