I have to admit I'm not a fan of basting often. I never baste my butts and I onyl sparingly baste my ribs. I like a good bark on my ribs.Like some of the other posters, spritzing them every half hour or so seems to be key in retaining moisture (but don't start this until the rub has formed a bark, usually 45 min to 1 hr into the smoke). I use 3 parts apple cider vinegar to 1 part olive oil. Removing the membrane should fix that "gummy" texture. ~225F at ~1 hr per lb has always worked for me with spare ribs, and as stated earlier, using rub the night before is key. They should sit for at least 12 hours in the rub to ensure good flavor penetration. I usually rub them with mustard and then use a homemade dry rub on top of that. Taking them out of the refrigerator 30-45 mins before smoking will help keep the smoker at temperature when you add them.
Squeeze butter (parkay) works well too if you don't like mustard.For pig-cicles only. Wash and pat dry, light rub with olive oil. Smear on yellow mustard, yes you read that right. You won't taste it. Sprinkle on garlic, black pepper, and almost any pork rub (I make my own). When that is good and rubbed in, spread on some black-strap molasses and rub that in. I like a fair amount.
Cook high over a red oak fire for about 2.5-3 hours. You won't believe it. Be careful with the black pepper, it will really come through.