I haven't got a chance to crank it yet but I'd like to ask a few qustions about the tubes I found in it. In the V positions all are mesa tubes except for V3 and V5 which are JJ's. Why would JJ's be in those positions. There are Groove Tubes GT 6L6 R in all 4 positions and Mesa 5U4GB in the other 2 positions. What do the groove tubes do that the stock ones don't? This is my first Roadster that is replacing my Triple recto. I'm not that familiar with Roadsters. If I put a Tung Sol in V1 like I did in my Triple will it improve the cleans?