Hi, I'm obviously new here but have been lurking on the rep forums for a little while. Just picked up a pure time 5517 to get my feet wet and have a couple questions that I haven't seen asked anywhere. People seem to be using ETA or DG movements that have close but not exact beat counts. I'm thinking I'll pull the ETA2846 out and use an old omega caliber 552 or 565 or 5xx, but I'm wondering why this isn't common practice. The 5xx has the exact same bph as the1520/1530 and is at least as accurate as the gen rolex movement. Has anyone done this yet? Size is very close on the omega as well, and obviously seamaster hands will fit since this is the engine in the seamaster 300. For anyone out there that's in the know, what problems do you foresee? i.e. is there some issue with adapting the winding stem to the crown or will the omega sit at the wrong depth? Thanks in advance for your insight. If things go well I may end up taking the $650 yuki case plunge and build myself a franken. Until then an omega powered rep sounds cool to me. Jake