Dehler has always been a very high quality boat company. They built both grand prix level race boats and a line of clever performance cruisers. The 35'' Dehler Optima is one of their performance cruisers and a boat that I have always like. I think that their fractional rig is really ideally proportioned for a 35 foot cruiser.
These are nicely constructed and nicely detailed boats. These are Van DeStadt designs. I have always been a fan of Van DeStadt as a company that does a nice job on detailing and engineering. These boats sail well and are good all around performers for a boat of this era.
In the down side, these are good but not great light air boats. They came with two different engines and the smaller 15 hp engine is a little underpowered in a chop and headwind. The head is forward in an area of rapidly decreasing headroom making the shower a little less than perfectly useable. Their hull design is influenced by late IOR hull thinking and so has a less than perfect motion in as seaway. Today, for a boat of this era, they are not the best race boats when compared something like a J-35 but they are more rounded boats than the J-35.
In stock form,they are a little short on water tankage but I believe that it should be easy to add a 20 gallon bladder typ ewater tank pretty easily.
All in all these are very nice boats at a typically reasonable priced under $40,000.