I fitted a resonated titanium Rev9 exhaust to my 2010 V10 R-tronic and have driven it spiritedly for 500 km. I bought it based on positive comments on this forum, videos available online, and perceived value for money. The exhaust is well-made and fitted pretty well, although the tips are very close to the top of the oval outlets in the bumper rather than in the centre.
The following is an objective assessment to the degree that I have no interest in promoting the brand (but it is subjective in terms of personal taste).
First impressions: very loud, a bit 'shouty' initially, to my ear at least. It felt like some of the mature, nuanced, V10-ness of the OEM had been lost.
Second impressions: very loud, but it quietened down a little with use and became less brash, the tone returned closer to the OEM V10-ness, and a delightful range of gorgeous burbles entered the mix when easing off the throttle. It is a very deep sound, and there is an added gunshot-style 'burp' on upshifts, which is addictive. It sounds much better at idle too.
Third impressions: wow, this thing howls in the upper rev range, it is quite something. Not an F1 sound as some have said (why would it be?) but definitely race car characteristics. And the throttle response is sharper, along with a feeling of more power and torque (Rev9 claim a modest 15hp increase). This may be a placebo effect due to the noise, but that's fine with me.
Overall, I am very pleased indeed, and the response from other R8 owners, including Gen 2, is nothing but effusive and highly positive. This exhaust has brought the car alive and given it a character that it lacked in the noise department. That said, it is always 'on' and certainly attracts attention, but if driven without big throttle inputs it isn't offensive.
As for drone, honestly, there isn't any...none at all. Those who complain of drone from the Rev9 seem to be V8 rather than V10 owners who have fitted the non-resonated track version of the Rev9. An exhaust without resonators is bound to have drone...
Taste is entirely subjective, but for my tastes, this has met the mark. I'd happily recommend the Rev9 resonated titanium version for the Gen1 V10.