Hello,
As one of the planets most vocal endorsers of Microcrystalline waxes I can assure you that Ren Wax is as good as you have heard. Ren Wax is a microcrystalline wax that contains White Spirit (the solvent you smelled). Here is a bit of chemical info on woodturnings "miracle wax" from an article I wrote on waxes for woodturners... (Complete article in my educational library)
Microcrystalline Wax is a petroleum wax containing branched and cyclic saturated hydrocarbons, as well as normal alkanes from deoiled residual bright stock lube oil streams. Microcrystalline waxes have a crystalline structure much smaller than totally natural waxes and have a very high resistance to moisture, alcohol, acids and fingerprints.
Microcrystalline waxes are obtained from the residual fraction of crude oil distillation (Petrolatum) or from crude oil tank bottoms. Hard grade microcrystalline wax (from crude oil tank bottoms) has a penetration of less than 11 dmm at 25 degrees Centigrade and a melting point of approximately 60 to 93 degrees Centigrade. Plastic grades of microcrystalline wax (from Petrolatums) have penetrations greater than 11 dmm at 25 degrees Centigrade.
The smell dissipates quickly and does not linger in the wood. Take care and all the best to you and yours!