Like the previous posters, I enjoy both. My SP-25 with an Infinity Black Widow TA has suffered at my hands since 1979 and is a great combo. As Mikkelbreiler states, the SP-15 has a reputation for damage to the shaft through forcing the platter off or from shipping with it on. The SP-25 is a stand-alone deck sharing components with the SL-1200 and is just about as bulletproof as it gets.
If you know a mechanic, borrow a gear puller, or, carefully insert wedges under opposite edges of the platter and gently tap the spindle, then retension the wedges. Light oil, heat with a hairdryer, lift evenly and tap is another suggestion. Make sure to unplug it, turning it on with the platter removed will likely damage the circuitry. Or, if it ain't broke don't fix it.