Is trixbox right for my business?

Thanks for any/all responses to my questions/concerns.

I have spoken to a local rep about setting up trixbox for my business and I think he is a nice guy with ADHD and may very well be new to trixbox.

Here are my business details:
1. Small business with 3 full time employee's plus myself.
2. Heavy phone useage as we are a sales/service business.

Here are my research issues and questions/concerns/needs:
1. I like the advanced features that trixbox has...Find Me in particular. I am out of the office on sales calls alot and hate calling in to check messages and/or having staff check my voice mail and email them to me... I also like the fact that calls can be transferred to my cell phone when I am out of the office......We currently have a Avaya Partner Plus system with automated attendant and voicemail.

2. I have done alot and I mean alot of reading over the past 3-4 weeks on VOIP and while I would love to save money by using voip as opposed to analog (copper) lines from AT & T...I have big concerns with quality. Some people I have spoken to say get a qos router and switch and you can use dsl at the high speed level. Other says under no circumstance should you do that...you need a dedicated T-1 line....there would go any potential savings if I go dedicated T-1.

3. I have a fairly new Dell box never used that I tried to load trixbox on and I was going to buy a couple of sip trunks and try the system out at home prior to using in my business, but I couldn't get past the first issue with install when the install was looking for drivers, sata, raid or otherwise....tried several times to no avail.... Called trixbox and while the guys where somewhat helpful, referring me to a wiki was not what I was looking for...I am fairly computer literate to the point that I can network and manage my own server and website.
I have read a couple of he white papers and was planning on running two sep networks..one for voice (dsl at 6.0 down / 768 up) and cable for my data...since you need 80-90kb per phone call I thought this might work.

So Do I:
Spend $1600 on the appliance and hope that it works as stated with analog lines? No savings but will get the functionality if it works properly...I feel somewhat insecure due to failed install and reading a ton of post on this site relating to installs. OR should I go with a hosted product that does the same thing and not have that expense?

I have bought a qos router (RV042 CABLE/DSL VPN ROUTER W/4-PT SOFTWARE 1 , qos switch (linksys LNK-SRW208) and 3 CISCO CP-7961G-GE phones. Like I said I was going to load trixbox on my new box and run the system at home on my dsl to get all of the bugs out prior to switching over to my office....CISCO phones apparently present another problem as one of the guys from trixbox told me they were hard to configure....

Sorry If this should like a ramble....I have written this between phone calls....

Any advice would be appreciated.