I had a verizon htc inspire 612 (which did have an lte sim slot) that I was able to register to straight talk cdma byop straight out of the box from best buy by registering the imei from the phone with a byop sim kit from walmart. There were verizon lte sim cards in the kit....and once the phone was active I put the sim from the kit in the slot and had instant 4g...and THEN a week or so later, obtained a US cellular samsung s4. I did nothing but take the SIM out of the 612 and put it in the s4 and I had full working service. Calls, sms, data , all of it. I sold the s4. Put the same sim back in the 612, same thing. Full service. THEN I bought a US cellular S3. Again, swapped over the sim and everything worked like a charm. It wasnt until I factory reset the S3 it no longer recognized the sim HOWEVER it DOES still recognize my friends SIM from her G3 that she has on verizon service and it will
Allow calls, sms and data. I was also under the impression that cdma sim cards were for 4g only but apparently this isnt the case. After speaking to all involved carriers I have come to the conclusion that none of them have the slightest idea what the hell they are doing...(big surprise) however, to answer your question, I would say buy the kit and put your service on the verizon SIM. This is a risk of course because I have absolutely no technical data to back this up... but this is how it worked for me so please do what you want with that info 🙂