The folding hardtop’s a matter of personal preference really I think; personally I much prefer that over the soft-top version not least due to the additional refinement the hardtop gives at motorway speeds with the roof up. After over 7 years of ownership I still really like my PRHT (Power Retractable Hard Top) & for me the purchase of this version as opposed to the soft-top car was a no-brainer.
As Raymond’s said, the seal between the back of the roof panel & the panel with the rear window can split on some older cars, the cause of this has been subject to some discussion e.g. possible rubbing on the carpet in the stowage area when the roof’s down, or possibly due to sun exposure when the roof’s up etc etc!
A very few folk have also had problems with the microswitches and / or motors; motor faults are very expensive to fix. Also the allen bolts can potentially work loose causing grinding noises.
Against these issues though, the soft top can also wear & need replacement, which isn’t a cheap fix either.
I think the general opinion is that the folding hardtop’s usually very reliable & generally trouble-free, although, like everything else on the car, the potential for problems will increase as it ages.
Other issues include the 2 scuttle retaining clip seals - these items are located beneath the small coin sized covers in the plastic panels at the bottom of the windscreen, they’re plastic clips which clip into the bodywork (with a foam seal beneath) & then the plastic panels screw down into those. The foam seals go & allow water into the cabin - on the nearside, the water often gets into the fusebox causing all sorts of electrical gremlins. The retaining clips are quite cheap & relatively easy to replace - I did mine a couple of years ago as a precaution.
A set of decent quality matched tyres is important - these cars are very sensitive to mis-matched tyres. Also check the radiator header tank, these can crack around the filler neck, underneath the cap causing a sudden coolant leak & overheating which may warp the cylinder head.
Electric window switches can also fail & on the model with the folding hardtop that affects roof operation because the windows automatically drop slightly before the roof starts to open or close, so if the windows don’t drop due to a switch fault then the roof won’t move.
As Raymond’s said though, the main thing to look for on these cars is underbody rust; there are some very good ones out there (garaged, rarely been out in the rain, possibly rust-proofed by a caring previous owner etc), but also some rough ones too which have racked up a relatively high mileage in all weathers without the application of any additional underbody protection.
There’s lots of good advice here on this forum!