I've built three rifles on Howa actions; latest one is a 260 Imp 30* with a 26" Krieger sendero contour in a McM adj. A5. Used PTG's new DBM on this build - wasn't able to get one of these units before McM was ready to do the inlet, so had to do the DBM inlet on the stock that'd been done for the factory hinged floorplate BM. I'm not crazy about doing inlet work, but this was a pretty simple, straightforward job, which took less than an hour to complete. BUT - I also had to mill part of the projection at the rear of the magazine cutout on the action in order to get the clearance needed to allow the magazine to latch-up, and to give the ctdg rims clearance to feed up out of the magazine. Still pretty simple work, but I'd hate to have to do it with a file or Dremel. However, when it was all said & done, it feeds like a champ, and the PTG unit's price is less than half what CDI charges.
I'd trued the actions of the first two Howa builds, but once I got them dialed-in, found there was very little need to do it. Just figured that since I'd spent the time & effort to get them dialed-in, might as well carry on. I leave one lathe set up with change gears to cut metric threads; it's sort of a PITA to do, since you have to leave the half-nuts engaged from start to finish when cutting metric threads on a lathe with an inch lead screw. I worried about that - especially when single-pointing the action threads - but once I got started, and kept distractions to a minimum, I had no problems with the job. I use T15 HSS threading inserts in an Arthur Warner Co threading bar, since carbide inserts will chip if you don't get them retracted from the work before you stop the spindle at the end of each threading pass. The T15 inserts result in a smoother cut than carbide at slower speeds, so it's a win/win situation as far as I'm concerned.
Whatever - the only downsides I see to using Howa actions are that the bolt lift tends to be a bit stiffer than a M700 or M70, and there are fewer aftermarket parts (compared to all the stuff out there for 700s). The new HACT trigger on the 260 I just finished is pretty good out of the box; I adjusted it down to just under 2lbs, with a good, crisp & clean break. The blued bbl'd actions require a cut into the bbl shank right up against the receiver face in order to be able to remove them - after the cut's made, you can usually unscrew the action off the bbl by hand.
I intended to sell this 260 Imp from the start; however, it shoots just fine, so if it doesn't sell at our club's annual gun show later this month, it's not gonna break my heart to keep it for awhile.
ETA - Added photo: CeraKote is sniper gray; can't see it in the photo, but I indexed a Harrell's tactical brake, which added about 1-3/4" to the bbl length. EGW 20 moa sloped rail mounts a Sightron SIII 6-24x50 LRMOA in TPS TSR rings.