I have been a Ford man all my days until I bought the Cup. My cars have ranged from race preped XR2s to show a show winning Escort RST.
In my opinion, I would go with an ERST, with the right mods will see 170bhp without spending too much cash. The only prob you will come accross is trying to find one that is a minter. Most are f**ked and their owners claim car park figures of 250bhp! Saying that, valvers are getting on a bit too, but I personally think that that dont give as much street cred as a polished RST.
Oh, and FRSTs go quick, but rot just as quickly.
I will prob be going back to Ford when I finish with the Cup. Good motor as it is for the money, A minted Escort Cos/new focus Cos, looks to be on the cards in the next couple of years.
Hope this helps,
Mac