Hi Jen and welcome.
I do not know anything about the Meg or the Claire, but I did pick up a Sweetone this past week and even though I own some more expensive whistles, the Sweetone isn’t going anywhere.
For the money, it’s a fantastic little whistle.
Good luck.
Mike
Perhaps this should be put in some kind of poll form, but this raises a question----
Do most folks who prefer Generations(or Sweetones/Clarkes) have other similarities in whistle preference? 
I know, for myself , I love Generations and DO NOT like Sweetones or Clarkes. 
The Bill Ochs book is the best one to start with. You can get it directly from Bill’s website:
Or you can get it for $0.95 less from Elderly instruments:
It also has guitar chords for those of you who play one, or have friends with whom you play along .
This is a book that I still use all the time even after having it a year! It will familiarize you with the tunes you will hear on your new, expanding CD collection of Irish traditional music that you will feel compelled to start buying. Then after you have many, many whistles, (in about 2 weeks from now) you will start casting around for a few new and different items, like say a flute or a bodhran or a mandolin or,or, aaaaaggghhhh
Welcome to the world of Chiff!
my favorite whistles when I started were Sweetone, and a Clarke
Mary
(Sorry for resurrecting old thread, but I don’t get online too often.)
I am completely broke at the moment, but I’ll remember the book tip for later on.
I was just wondering, how did people really get into the ‘whistling-thingie’? I have a booklet with a CD, but I didn’t really think trying to squeeze tones out of my whistle was any fun until I put on a DVD of mine and played along with the whistle player there. I found what I considered to be the easiest song to play along to, and did that - and it was a lot more fun than to sit down and listen to this guy tell me how to hold the whistle and play a lame jig 
I have that too - good book (I got that last fall, when I was in Ireland) but much better with the CD (got it recently from the Whistle Shop). But it isn’t really a tutorial. A plus is that the pieces on the CD are played in a fairly traditional style, but it assumes from the start that you can play the whistle at a solid beginner level and read music.
The Bill Ochs book can be picked up online, from Bill himself or the Whistle Shop (officially, this is the “Clarke Tinwhistle Tutor”). VERY good book for the beginner, since it starts with the basics. Though I’ve picked up a lot of pieces elsewhere (Walton’s 101, A Dossan of Heather, others) I’ve been working my way steadily through it, memorizing each piece as I go - currently working on “Rufty Tufty”.
A possible negative if you’re mostly interested in IrTrad is that most of the early pieces are NOT Irish, and are not played in an IrTrad style - ie, no ornamentation, each note is tongued unless explicitely slurred, etc. (He does cover Irish tunes, and the IrTrad style, later on). But this is a minor quibble - if you can work your way through the book to the end and master every tune in it, you’ll have the foundation to play any tune you want. Highly recommended.