Stock Data is not slow to load. But I agree with @maxinger, you truly need to do your own research based on your own specific needs, and find what best fits you as a trader, and your budget. Lots of options these days. Back when I began in 1998, I had my own Bloomberg Terminal at $2K a month, which I now consider incredibly stupid!
I tried integrating esignal data feed into TWS even with the 32-bit version, didn't work. Copied some DLL as IB instructs in their troubleshooting guide, didn't work. Plus, they are the only vendor I've tried that charges VAT (20%) on top of their fees (I live in the EU). It seems too pricey just to use their standalone, asked for refund. I feel that established data vendors have become complacent: outdated software, website or user experience. Modern solutions like TradingView are eating into their marketshare and are facing a slow death if they don't adapt fast. Btw, TV has a standalone app now. IB already integrates their charts into the web platform.