I'm looking at the same bike although the "SLR01 One" model as I can only afford Ultegra Di2 :)
My guess would be that there would only be minor differences to the 2019 model since the 2018 when thru a more significant change from the 2017 design.....could always be wrong. All depends on you needs and wants.

Now if you were asking about say the Trek Madone......that bike will probably see some changes for 2019 mainly a disc model so if that's one you were looking at I might say hold out for a bit.

Didn't BMC just update the SLRbfor '18? If so I cant imagine any changes beyond colors. 8000/9100 are still early in life so I wouldn't expect any new Shimano releases or other spec changes that are worth holding off on. If you can get a good deal now, go for it. If you are waiting for other bikes, the only big one I can see coming out is the Madone Disc which will probably debut at TdF.

I just got one myself - picking it up tomorrow! :)

I got the frame module though and am swapping components/building it up. I considered ordering the complete bike, but there weren't any more available in my size (51) until the new models come out. You may be in that same boat unless you've already checked availability. I didn't consider waiting since they just did a refresh on the frame. I imagine the only change will be colors since Shimano isn't releasing anything new next year.

The SLR series was literally just updated. I was eyeing new bikes all last summer and ordered the SLR02 "Disc-One" late September I think. It was mid November before it had shipped from BMC to my dealer in the San Francisco area. I don't know if they typically release on that pattern, but for a model that just started shipping in November or so, you might be waiting a while for the next version if you hold out.

Btw though, +1 on the SLR series. I'm still in love w/ mine. I like it way better than my TM01!

Rode mine for the first time yesterday. Granted it was only a short ride, but I'm impressed. I'm coming from the new model R5, and the SLR01 is hands down a better bike. I didn't feel like I lost anything accelerating, but I was blown away at the compliance. Small bumps almost felt invisible. Definitely a marked difference - and that lines up with what a lot of reviewers had said about it also.

Firts: thx for the replys. Helped me a lot in my decision.

I just bought a slr 01 grey black with disc brakes. Superhappy with my choise and u guys helped me very good. Thx and ride on! 😀