I had a Renaissance MKIII.
I recommend a high efficiency speaker like the Avantgarde Duo or a Lowther based speaker or equivalent. Thirty watts is really not a whole lot of power, and even though these speakers play loudly with much less, to my ear they really open up if the amp has some headroom. With these the VAC will be loafing along the majority of the time yet has the power to hit transient peaks with ease. On the other hand if you get a less efficient speaker it will quickly run out of power on the transients.
Good luck with your search.