I hardly think you would have any compression issues with just 150 hours. I've got a 650 with 350 hours, and another 650 with 240 hours. The 350 hour engine, it's on my shop floor awaiting a rebuild. It ran great and pulled hard before I pulled it out for no reason other than to give it a break.
It burned a little bit of oil, but not enough to warrant adding any between oil changes. I changed it at closer intervals as the hours piled up though. (6-8 hours with rotella t)
It smoked a tiny bit at high throttle, and was only visible at night with someone following me.
They both have had a valve train refreshment. Valve seals, timing chain, **cam follower bearings, *dual valve spri gs, and a new head gasket.
** (needs at least a thourough inspection or advise replacement every 90-120 hours of use)
* (said to give the valve train components an easier time)
Both bikes have a high speed check valve plumbed into the front valve cover outlet. The rear is blocked off. I did that after constantly finding oil in the airbox and also the telltale puddle between the carb and the intake boot. Oil consumption went down to almost nothing when I installed the high speed check valves.
More on that here; crankcase venting 101
viewtopic.php?f=5&t=1110