Been playing with Solana a lot more lately, but price quotes are sluggish, 50% of my trades fail, trades take ~15 seconds to complete, and I have to break my trades up into much smaller increments to get them through. 

Any tips on how to get a better experience here? Moved my slippage up to 1% and that helped.

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I’ve been trying to cash out of WIF on Raydium for about 3 days now and can’t get the swap to work, even with slippage as high as 20%

More or less having the same experience as you

Yeah, Raydium is hot garbage. Use Jupiter instead, it'll get you the best results (it's an aggregator & includes Raydium anyways). Update your priority fee setting in Jupiter, either set to "turbo/ultra" or (as I do) set the max cap to 0.0005 SOL (~9 cents), slippage to 1.5% on WIF should suffice, maybe 2% max