Take others with you and sit in and walk around in models with and without a slide. Imagine it raining and cold out and staying inside. Spending that much money I would put a whole lot of thought into this if you are unsure. If you were spending 3 or 4 thousand and decided you didn't like it, you could turn around and dump it for a small loss. If you bail on a new one soon you will take a big hit.
Like others said, not only rent one to try it but maybe rent one as the only way you use one. Then you get into all the hitches, tow vehicle, accessories, insurance, storage etc.