That great money saving deal Comcast and Roku announced Tuesday for Xfinity TV subscribers might not be so swell after all.

As spelled out in the Xfinity TV Beta App on Roku FAQ, there is no such thing as a free box, even when replacing a $9.95 a month leased cable box with a Roku streaming media box playing the same content through the new Xfinity TV Beta App.

At launch, beta testers must have at least one Comcast receiver or cable card in place to activate Roku receivers elsewhere in their home, "due to [current] technical limitations," as stated in the FAQ. Later, that situation will likely change.

For receiving their shows on other TVs, the guinea pigs will have to buy a Roku stick, receiver box, or television that has the Xfinity TV app installed. Costs range from as little as $29.99 for a Roku stick to about $300 for a 50-inch high-definition Roku TV (from brands like Sharp, TCL, and Insignia.)

During the beta-test phase, participants will then get a full pass on Comcast's usual second (third, fourth, etc.) set cable box "outlet fees." But only temporarily, maybe for a few months or a year. Once the Xfinity TV service is debugged, fine tuned and officially launched, additional outlet charges will kick in, cautions the FAQ.

"Customers will not pay equipment charges with respect to their use of Roku devices. All other fees associated with a customer's service will apply, except that, during the beta trial, additional outlet charges for services to outlets connected to Roku devices are being waived. On conclusion of the trial, you will be informed of the charges that will apply for connecting this device with your Xfinity TV service and will have the opportunity to opt in."

How much could that be? Xfinity cable subscribers who currently substitute a TiVo recorder empowered with a CableCARD (leased from Comcast) pay a "net" outlet charge of $7.45 per month. That's discounted $2.50 from the outlet charge when using a Comcast box. At least the same level of saving is likely to apply for Roku-connected customers.

(Currently, there's no outlet charge for the first cable box bundled with a subscription, and a $2.50 credit is offered if substituting an alternative-tuning device like a TiVo. Another way for cable customers of Xfinity, or rival services, to save even more on box fees is to install a streaming TV receiver like a Roku on secondary set locations and then individually authenticate many of the basic and pay channels which they subscribe to. In that scenario, they lose out on the integrated X1-style program guide and search functionality available with the Xfinity TV app.)

Bean counters at Comcast might decide that the outlet charge should be even lower for customers using the Xfinity TV app on a Roku box. Especially if the customers decide to crank up their internet service, thus paying Comcast more, to enjoy the higher resolution, higher data rate for 4K Ultra HD versions of Netflix and Amazon Instant Video, which are also available on pricier ($99+) Rokus.

Beta adopters' enthusiasm, or lack there of, for the new option might also play into the pricing as Comcast does a lot of variable "see what the market will bear" test pricing. In towns like Atlanta and Nashville where there's more internet service competition, such as Google Fiber, Comcast now offers gigabit internet service for $70 a month with a three-year contract. In other towns, the no-contract going rate is $139.95.

Unfortunately, Philadelphia is not on the latest list of "upcoming" service zones getting the new DOCSIS 3.1 (data over cable service interface specification) system upgrade which can increase internet download speeds to 1 GB while upstream flows hold at about 35 Mbps.