starting a DISCUSSION here on VPN (Virtual Private Networks)

Please stress that this is a DISCUSSION... it is NOT a recommendation.

I was surfing the web, and came across a "recommendation" by Kim Komando to consider using a VPN : Virtual Private Network, specifically, for connecting to a wireless hot spot [like at a hotel, restaurant, public library, &etc].

http://www.komando.com/downloads/category.aspx?id=6161

"Public networks (both wired and wireless) are great. After all, what would life be without connecting while at airports, hotels and coffee shops? However, the danger to your personal data exists even if you connect to a fee based open network. Your passwords, credit card numbers, and any data you send can be seen and associated with you personally. Standard antivirus software won't protect you as this threat is on the network, not your laptop....

a virtual private network (VPN) [set up] between your laptop... and [an] Internet gateway [creates an] impenetrable tunnel [that] prevents snoopers and hackers from viewing your email, instant messages, credit card information or anything else you send over the network".

The particular product suggested by Ms. Komando is AnchorFree's HotSpot Shield, http://hotspotshield.com/  (from which the above italicized  text was quoted).

There's an immediate PRO and CON to consider about this particular choice:   PRO:  it's free.   CON:   It's ADWARE-sponsored --- banner advertisements will appear toward the top of your screen, while the VPN is active.    (Many of you will rightfully reject this product on that basis alone)

Ms. Komando's contention is that, since you won't be running VPN from your regular/home/work networks, but rather, only while you're on the road at wireless hotspots, for the limited times you have to do so, the banner ads are an acceptable "price" to pay for this extra security.

In terms of "luggage", HotSpot Shield adds a BHO (Browser Helper Object) to IE, as well as a Service and Helper Service that each auto-boot.

Questions for debate and discussion:

1)  How effective are VPN products at doing what they claim:   e.g. do they really protect you if you enter your credit card account numbers (and similar highly-sensitive information) at a wireless hotspot?   And does using them slow transmissions down, or use excessive CPU/RAM?

2a)  Does anyone have first-hand, specific experience using HotSpot Shield?

2b)  Does anyone have first-hand, specific experience using some other VPN software?   Which one(s)?  Please be sure to indicate whether they are completely free, adware-sponsored, or paid products.