Curved OR straight Rega arm

I'm looking at a used Rega P2 and P3. Both have curved arms. Is this a drawback? Are the straight arms an improvement?
Any opinions would be appreciated.
I think the Rega straight arms were definitely considered an improvement,the RB 300 was revolutionary in it's day.That said people still like the curved arms and consider them very good.
I'd strongly recommend getting the later Rega table with the straight tonearm. The later Planar 2 had an RB250 on it, and the later Planar 3 had the RB300 on it.

The older curved arm was not in the same league as these other 2 arms.

That being said, if you plan to use a relatively low cost mid-compliance MM cartridge on it, the curved arm should do reasonably well in that role, but never up to the same standard as the straight Rega tonearms.
Neither the P2, nor the P3 came with "S" shaped arms. Only earlier versions of the Planar 2 amd Planar 3, which are differnt turntables. The Japanese sourced "S" shaped arms, RB200, on the older turntables are inferior to the later Rega made RB300 and RB250 found on later production Planar2 and Planar3, and all P2 and P3 tables.