Is there any other instrument where you you can pay around $20 and get something that actualy plays (or more to the point can be played)beautifully? Is a recorder better? Listen to a great whistle player you know that the apparently limited note vocabulary does not keep them from expressing themselves or playing anything they care to.

I have a number of whistles and I find the Sweetone ($8) is rather hard to play, I prefer the Original Clarke even if it is $5 more.
I have been pleased with all my D & C Susatos ($18), bought a bummer of a Susato Low D the holes were irregular and erose in spots and just hard to play. ($35)If I ever find the factory I'll wqalk in and ask for a refund On the other hand I bought a low F Susato that plays (Or I Can Play) like a charme.
Have not cared for thew Acorns I have Bought ($12), but the Aluminum Low G Chieftan my wife gave me ($120) has a great sound.

As it has been said the key to geting the whistle to work well is breath controll. A most common problem is starting out blowing to hard so you might be in a higher octave when you start. You can get 3 octives out of most whistles but the top one rarley sounds good. I found it useful to think of blowing "faster" rather than "harder" to go up an octave, semantics I know but like with golf instruction it is a "Feel" thing....errr not that anyone asked!