I own a 205 gti too
Maybe I can provide some objective opinion, im a newbie too and own an a3 tdi 130 boosted by a cheapie celox box (£27 off ebay!) and a 205 gti 1.9. Ive performance tested both (my a3 compares with a 150 old shape leon tdi) and I reckon the 205 will only win against an FR tdi off the line and maybe in 2nd gear. the 205 was hot in its day but unless yours is a minter, they're getting on now and i reckon the FR will eat the 205 from 0-100, 30-70 through the gears, 50-70 and so on. The Leon will also have more grip, remember the old pug is only on 15 inchers. What the leon wont do is change direction as well, feel like a go cart or give such an adrenalin hit every time you drive it. But then ive driven modern clio 182's etc and they're not as much fun either. The 205 is unique and the Leon is a totally different animal. I want one of those too, but not to replace the 205! Not sure if this helps or confuses! Keep the pug as a classic and buy the FR as a daily driver!