i bought both a t34.48 and a t34.63. i kept the .48 on as it was more usuable for quick get aways with boost coming in at about 1400rpm compared to about 2500rpm on the .63. acceleration rather than top end was my main concern.
i had nothing but bother with recon turbos and only fixed it properly when i bought one brand new from woodford garage for about £800 for a stage 2 t34.48. obviously not all turbo recons are shoddy but 3 fook ups and redone rebuilds in under a year put me off.