If your budget runs to a 313HR, then yes it is well worth imo.
Just be careful when yu are looking for ads that say "facelift" as that can (and more often does) mean the 2006 rev-up that was introduced in March 2006 and unsold stock carried on being sold into '10 plates, as the 313Hr was introduced in 2007. Also many earlier 350's have had HR 'bulge' bonnets fitted as a desirable mod an some new buyers have been caught out........not helped by too many dealers either not knowing the difference (being generous with that description) and/or going solely by registration date.
The HR engine can cope with up to 500bhp and more on standard internals, whereas the earlier engines are more restricted, unless forged.
But in standard form there is naff all difference between the models on the road, speaking as someone who has had all 3 engines, albeit the HR engine in my case was in a 370 which has a little more bhp than the 350HR.
Good luck with your search