When two boats share the same hull type — in this case both the Weld-Craft 1648 Stick 2011 and the Weld-Craft CDS 36 (14 ft.) 2009 are flat designs with aluminum construction — the buying decision usually comes down to a handful of practical questions: how many people are you putting on the water, how far do you trailer, and what does your tow vehicle weigh?
Both boats share a closely matched power ceiling — 40 hp for the Weld-Craft 1648 Stick 2011 and 20 hp for the Weld-Craft CDS 36 (14 ft.) 2009. Real-world performance will come down more to which motor is actually bolted on, its load at the time, and whether it's a 4-stroke or 2-stroke setup.
Bottom line: Performance buyers should lean toward the Weld-Craft 1648 Stick 2011 and its 40-hp ceiling. If fuel economy and quieter running matter more than top-end speed, the Weld-Craft CDS 36 (14 ft.) 2009 with its 20-hp rating is the more economical daily driver.