Hi There!
It all depends on how much your friend wants to spend, of course. The problem that I have with Yamaha "student" instruments is that several alternatives exist which offer better value and an equal/better sound quality. In the sax world Bauhaus Walstein produce excellent saxes - with an alto available for under £400 new compared to the YAS 275 which is often around £800+. Also Hanson, also John Packer are very good quality just MUCH cheaper. He could buy a BW Alto AND Tenor for less than a 275.
Similarly in the Brass world - the Yamaha 354 Trombone is considered the student benchmark, but the John Packer231/Rath Trombone is easily its equal and more. Cost of the Yamaha is £520+, whereas the JP231 is £350. There are similar examples with trumpets/cornets and others (I won't bore you with the details, but there are similar stories to be had). The point for me is that Yamaha student instruments are good quality but not as good value as several alternatives or as good sound wise. If Yamaha was the way to go 10/15 years ago I would say that things move on.
So, I would recommend the above as options - BW are available at Woodwind & Brass (Hants), Sax Heaven (Oxford) and Studio Saxophones (Abergavenny) all of which do mail order. Hanson are available by mail order, and John Packer are based in Taunton (also online)
The other thing would be that there is no reason why your friend shouldn't start with a pro horn (YAS 62, Yanigasawa A901 -plenty of others around) as it can be a false economy buying a beginner, then intermediate, then pro horn - unnecessary commercialism at times.
If it was me starting, with a high level of commitment, I would probably get a BW, and may/may not upgrade in several years time. Once you are hooked you may just want to buy another sax anyway, whether or not you need one!
I hope this helps.
Kind regards
Tom